Endometrial Cancer Flashcards
What is endometrial cancer?
What are most cases?
- cancer of the endometrium (lining of the uterus)
- 80% cases are adenocarcinoma
- it is an oestrogen-dependent cancer
oestrogen stimulates the growth of endometrial cancer cells
When should endometrial cancer be presumed?
- any women presenting with postmenopausal bleeding has endometrial cancer until proven otherwise
- diabetes + obesity are key risk factors
- 90% cases are in women > 50
- 4th most common cancer in women
- > 75% 5-year survival
What is endometrial hyperplasia?
- a precancerous condition in which there is thickening of the endometrium
- most cases return to normal, but 5% become endometrial cancer
What are the 2 types of endometrial hyperplasia?
endometrial hyperplasia without atypia:
- the cells appear normal-looking and are unlikely to become cancerous
atypical hyperplasia:
- there is an increased risk of cancer as cells appear abnormal
How is endometrial hyperplasia treated?
- it is treated with progestogens
- the intrauterine system (e.g. Mirena coil) can be used
OR
- continuous oral progestogens such as levonorgestrel
What are the risk factors for endometrial cancer related to?
- the risk is associated with the amount of unopposed oestrogen the endometrium is exposed to
- unopposed oestrogen is oestrogen without progesterone
- unopposed oestrogen stimulates the endometrial cells and increases the risk of endometrial hyperplasia + cancer
What risk factors are associated with an increased exposure to unopposed oestrogen?
- increased age
- earlier onset of menstruation
- late menopause
- obesity
- no / few pregnancies
- oestrogen only HRT
- tamoxifen
- polycystic ovarian syndrome
- obesity is a RF as oestrogen within the fat stimulates the endometrium
- smoking slightly reduces the risk
What are the 4 different types of endometrial cancer?
- adenocarcinoma (endometrioid type) - 90%
- serous papillary carcinoma (5%)
- clear cell carcinoma (4%)
- sarcomas
Why is PCOS a risk factor for endometrial cancer?
- there is increased exposure to unopposed oestrogen due to a lack of ovulation
- ovulation results in the production of a corpus luteum
- the corpus luteum produces progesterone during the luteal phase
- without ovulation and a CL, there is no production of progesterone and the endometrium is exposed to unopposed oestrogen
How is the endometrium protected against unopposed oestrogen in PCOS?
- women should have one of:
- intrauterine system (e.g. Mirena coil)
- combined contraceptive pill
- cyclical progestogens to induce a withdrawal bleed
Why is obesity a risk factor for endometrial cancer?
- adipose tissue is the primary source of oestrogen in postmenopausal women
- adipose tissue contains aromatase
- aromatase converts androgens into oestrogen
- more adipose tissue = more androgens converted into oestrogen
- the oestrogen is unopposed after the menopause in women who are not ovulating
- this is because there is no corpus luteum to produce progesterone
What are the risk factors for endometrial cancer not related to oestrogen exposure?
- type 2 diabetes
- hereditary nonpolyposis colorectal cancer (HNPCC) or Lynch syndrome
Why is T2DM a risk factor for endometrial cancer?
- there is increased production of insulin
- insulin stimulates the endometrial cells and increases the risk of endometrial hyperplasia + cancer
What are the protective factors for endometrial cancer?
- combined oral contraceptive pill
- Mirena coil
- increased pregnancies
- cigarette smoking
What is the main presenting symptom of endometrial cancer?
!! postmenopausal bleeding !!
- this is bleeding occurring at least 1 year after cessation of periods
- 10% of women with PMB will have malignancy
How do premenopausal women with endometrial cancer typically present?
very heavy, irregular or intermenstrual bleeding
What are the other presenting features associated with endometrial cancer?
- haematura
- postcoital bleeding
- intermenstrual bleeding
- unusually heavy menstrual bleeding
- abnormal vaginal discharge
- anaemia
- raised platelet count
What examination is performed in suspected endometrial cancer?
speculum:
- used to exclude other causes such as cervical / vaginal lesions
bimanual examination:
- a fixed or bulky uterus may be felt in advanced disease
When do NICE reccommend urgent referral in endometrial cancer?
- postmenopausal bleeding occurring > 12 months after last menstrual period
- should be referred via the 2WW pathway
When do NICE recommend referral for transvaginal US in women > 55?
- unexplained vaginal discharge
- visible haematuria + raised platelets, anaemia or elevated glucose
What are the 3 investigations used in diagnosing / excluding endometrial cancer?
- transvaginal ultrasound
- pipelle biopsy
- hysteroscopy + biopsy
How is transvaginal US used to exclude endometrial cancer?
- it assesses endometrial thickness
- normal thickness after the menopause is < 4mm
- if thickness is > 4mm, further investigations are performed
- this is harder to perform on premenopausal women as the endometrium may be thickened if they are about to have a period
- biopsy is usually performed for certainty
What is involved in a pipelle biopsy?
- a thin tube (pipelle) is inserted through the cervix into the uterus with a speculum examination
- the tube fills with a sample of endometrial tissue
- this can be examined for signs of endometrial hyperplasia / cancer
Who is suitable for a pipelle biopsy opposed to hysteroscopy?
- suitable as a quicker + less invasive alternative in low-risk women
- can be performed as an outpatient
What investigations are required to discharge a patient with a very low risk of endometrial cancer?
- a normal transvaginal US with endometrial thickness < 4mm
AND
- normal pipelle biopsy
Where does endometrial cancer typically spread to?
direct spread:
- cervical stroma
- fallopian tubes
- ovaries
across peritoneal cavity:
- omentum
- surface of liver / bowel
bloodborne:
- liver + lungs
Which lymph nodes does endometrial cancer tend to spread to?
- pelvic nodes
- para-aortic nodes
- inguinal lymph nodes (RARE)
How is endometrial cancer staged?
FIGO staging:
stage I:
- confined to the uterus
stage 2:
- involves the cervix
stage 3:
- spreads outside of the uterus to the lymph nodes, vagina, fallopian tubes or ovaries
stage 4:
- involves the bladder / rectum or distant spread beyond the pelvis
What is the treatment for stage 1 or 2 endometrial cancer?
total abdominal hysterectomy with bilateral salpingo-oophorectomy
- known as TAH and BSO
- removal of the uterus, cervix + adnexa
